FRISCO — Grizzly bears, once ranging 100,000 strong, once ranged widely through western North America, from the Arctic down to Mexico and from the Pacific Coast to the Great Plains. The mighty predators have disappeared from most of their historic territory, but there’s no reason they couldn’t make a comeback, according to wildlife advocates with the Center for Biological Diversity.

The group, best known for working ceaselessly to protected endangered species, has filed a petition with the U.S. Fish and Wildlife Service to greatly expand its plans for recovering grizzly bears. Preliminary studies suggest there are at least 11o,ooo square miles of potentia habitat in places like the Gila/Mogollon complex in Arizona and New Mexico, Utah’s Uinta Mountains, California’s Sierra Nevada and the Grand Canyon in Arizona.

Outside the Yellowstone and Northern Continental Divide populations, very little progress has been made recovering grizzlies. Remaining populations cover an area that is a mere 4 percent of the bears’ historic range and only 22 percent of potentially suitable habitat identified by researchers.

Returning bears to some or all of these areas is a crucial step toward recovering them under the Endangered Species Act and could potentially triple the grizzly bear population in the lower 48, from a meager 1,500 to 1,800 today to as many as 6,000.

“Grizzly bears are one of the true icons of the American West, yet today they live in a paltry 4 percent of the lands where they used to roam,” said Noah Greenwald, the Center’s endangered species director. “We shouldn’t be closing the book on grizzly recovery but beginning a new chapter — one where these amazing animals live wherever there’s good habitat for them across the West.”

The petition calls on the Service to revise its 1993 recovery plan to include suitable grizzly habitat across the West and to incorporate the findings of recent research that raises questions about the long-term viability of current grizzly bear populations, under relentless pressure from climate change, invasive species, human population growth, and related conflict and mortality.

Since grizzly bears were listed as a threatened species under the Endangered Species Act in 1975, the Service has pursued a fragmented approach to recovery that fails to meet the intention of the Endangered Species Act to recover species across significant portions of their historic range.

To date the agency has developed recovery strategies for only six populations, living in a relatively small portion of the bears’ range, including the Greater Yellowstone, Northern Continental Divide centered on Glacier National Park, Cabinet-Yaak, Selkirk Mountains, North Cascades and Selway-Bitterroot. And for the most part, the agency has only carried out on-the-ground recovery efforts for the first four populations.

“The good news is that with the safety net of the Endangered Species Act, the health of Yellowstone and Glacier area grizzly bears has improved — but it’s way too early to declare victory and walk away,” Greenwald said. “All remaining populations are isolated, especially Yellowstone. Yet the science is clear that, if we’re serious about recovering grizzly bears, we need more populations around the West, and more connections between them, so they don’t fall prey to inbreeding and so they have a chance of adapting to a warming world. If we want these incredible bears around for centuries to come, we’ve still got a lot of work left to do.”

According to the petition, the Service’s failure to develop a plan for recovery and conservation of grizzly bears across significant portions of their historic range ignores the important ecological role they play in ecosystems and the fundamental conservation principle that the preservation of a species and its habitat over the long term depends on numerous connected populations across the landscape.

A comprehensive grizzly bear recovery plan that meets the requirements of the Endangered Species Act would establish specific landscape-wide population recovery targets capable of sustaining the species across its historic range; it would protect grizzly bear habitat holistically, allowing the bear to weather threats from global warming, nonnative species and human population growth.

Precedents for successful recovery plans that include species’ entire ranges in the United States include those for the bald eagle, brown pelican and peregrine falcon.

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